Mold making equipment utilizing vertical mold blowing and plural rammers

ABSTRACT

Bottomless cope and drag boxes mounted on a turntable are cleaned, assembled upon a pattern plate, turned on edge and clamped between closure platens and filled with molding sand. The platens are then advanced into the boxes to compress the sand against the patterns to form molds. Upon withdrawal of the platens, a sprue hole is made, the assembly is rotated to horizontal, and the boxes and contained molds are separated from the pattern plate, which is then withdrawn. After insertion of cores, if any, the boxes and molds are reclosed. An elevator rises through a withdrawal yoke into engagement with the mold whereupon a complementary platen opposing the elevator forces the sand mold downwardly from the boxes and into the plane of the yoke to the level of a withdrawal table onto which the yoke draws the mold, leaving the boxes empty for repetition of the process.

United States Patent Harrison E. Fellows [72] Inventor 2,933,785 4/1960Hansberg 164/200 X Clearwater Lake, Wis. 54518 3,030,675 4/1962Chiabotti 164/200 [21] Appl. No. 790,072 3,229,336 1/1966 Hunter etal164/182 X [22] Filed Jan. 9, 1969 3,303,535 2/1967 Rearwin et al 164/172[45] Patented June 29, 1971 3,406,738 /1968 Hunter 164/183 X 3,433,2853/1969 Fellows 164/193 [54] MOLD MAKNG EQUWMENT UTILIZING PrimaryExaminer-J. Spencer Overholser a MOLD BLOWING AND PLURAL AssistantExaminer-John E. Roethel RAMMERS Attorney-Wheeler, House 84 Clemency l 1Claims, Drawing Figs.

U.S. Bottomless cope and drag boxes mounted on a 164/22. 4/37, 164/ 181164/182, 1 turntable are cleaned, assembled upon a pattern plate, turned164/201 on edge and clamped between closure platens and filled with [51]llll. Cl 8221C 15/28 molding and The platens are then advanced into theboxes to Field 0' Search 164/169, compress the and against the patternsto form molds, Upon 133, withdrawal of the platens, a sprue hole ismade, the assembly 324, 325, is rotated to horiaontal, and the boxes andcontained molds 326, 327 are separated from the pattern plate, which isthen withdrawn. References Cited After insertion of cores, if any, theboxes and molds are reclosed. An elevator rises through a withdrawalyoke into en- UNITED STATES PATENTS gagement with the mold whereupon acomplementary platen 2,049,967 8/1936 Luton 164/181 opposing theelevator forces the sand mold downwardly from 2,317,574 4/1943 Williams164/181 the boxes and into the plane of the yoke to the level of a2,791,012 5/1957 Miller 164/181 withdrawal table onto which the yokedraws the mold, leaving 2,882,565 4/1959 Selby 164/201 the boxes emptyfor repetition of the process.

STATION I la S'I'A'T'iON 11 sTAnoNm STATtON J2 PATENTED JUNE 9 I97;

SHEET 2 BF 7 ATTORNIE PATENTEI] JUN29 1971 3 5 9 ',43 .1

' sum u or 7 INVENTOR Hneeawv E. Flex 4 a w s ATTORNEY) MOLD MAIKGEQUIPMENT UTILIZING VERTICAL MOLD BLOWING AND PLIJRAL RAMMERS BACKGROUNDOF INVENTION This application is a companion to my application Ser. No.476,090, filed July 30, 1965 and now U.S. Pat. 3,433,285, issued March18, 1969.

There are molding machines which produce a drag mold and then roll overto make a cope mold. The disadvantage of such devices lies in the factthat the drag mold is made against an unsupported pattern which willdeflect under some conditions. It is also known to make both moldssimultaneously by filling the form through the drag cavity from theside. In such devices of this character as I am acquainted with, thesand from an overhead magazine has to be forced through a bent pipe orconduit to enter the drag cavity in this manner and there isconsiderable friction and sometimes inadequate filling.

SUMMARY OF INVENTION The limited rotation of the mold boxes in theinstant device presents the mold cavities simultaneously to separatefiller spouts to receive sand directly from overhead magazine means ofthe type disclosed in my prior application above identified. Thecompression of the sand in the respective boxes also occurssimultaneously by platens operating equally and oppositely to giveuniform mold density in the respective boxes.

The boxes within which the molds are formed are attached to operatingrams and slidably mounted in guides having trunnions pivotally carriedby arms cantilevered from the indexing table. This arrangement permitsthe parts to be in the desired position, whether it be vertical orhorizontal, at the respective stations, hydromotors preferably beingused to effect the required bodily rotation on the trunnions.

For withdrawing the finished molds, a yoke embracing the molds travelsacross a withdrawal table. The molds are I lowered to the level of thetable on an elevator which rises BRIEF DESCRIPTION OF DRAWINGS FIG. I isa diagrammatic plan view of parts of mold making equipment embodying theinvention, the super structure being removed to expose most of themechanism at the level indicated by the line 1-1 of FIG. 2.

FIG. 2 is a diagrammatic view taken in section on the line 22 of FIG. I.

FIG. 3 is an enlarged detail view showing in side elevation thestructure at Station II.

FIG. 4 is a view in vertical radial section through the mold fillingstructure in FIG. 3.

FIG. 5 shows fragmentarily the parts of FIG. 4 when the platens areadvanced to compress the sand in the boxes. 4

FIG. 6 is a fragmentary detail view on an enlarged scale taken insection through one of the vent fittings.

FIG. 7 is an enlarged fragmentary detail view in generally horizontalsection through the parts of Station I.

FIG. 8 is a view in perspective fragmentarily illustratingdiagrammatically and in mutually separated positions the mold boxes andassociated parts.

FIG. 10 shows the pattern plate advanced to position between theseparated mold boxes at Station I.

FIG. II shows the mold boxes closed upon the pattern plate at Station I.

FIG. 12 shows the open ended mold boxes and pattern plate assemblyrotated to receive the sand through the ends of the boxes at Station II.

FIG. I3 shows the closure plates advancing to close the open ends of themold boxes to provide closed chambers into which the sand can be blownat Station I].

FIG. 14 shows the boxes closed and the sand being delivered into themabout the pattern as at Station II.

FIG. 15 shows the sand within the boxes being subjected to compressionagainst the pattern as at Station II.

FIG. 16 shows the sprue hold formed in the sand of one of the boxes, thepressure plate having been withdrawn and the boxes remaining on edge.

FIG. 17 shows the boxes restored to horizontal positions as at StationIII.

FIG. 18 shows the boxes separated to expose the pattern plate andpatterns to the ram which is about to force the pattern plate back tostored position at Station III.

FIG. I9 shows the pattern plate in stored position to which it has beenforced by the extended ram at Station III.

FIG. 20 shows placement of the cores in the sand mold at Station IV.

FIG. 21 shows the two sections of the sand mold closed upon the core atStation IV.

FIG. 22 shows the closed molds and boxes above the path of the dischargeyoke at Station V.

FIG. 23 shows the elevator raised through the discharge yoke intoengagement with the lower section of the sand mold, the completed moldbeing held against the elevator by the opposed pressure plate at StationV.

FIG. 24 shows the upper pressure plate acting on the sand mold to pushit from the boxes and to lower it on the elevator elevated molding boxesempty for cleaning and reuse at Station I.

DESCRIPTION OF PREFERRED EMBODIMENT The number of working stations aboutthe turntable 2 may be varied to suit the requirements. In the instantdisclosure, there are five stations designated by roman numerals I to V.

The annular turntable 2 has rollers 3 guiding it for rotation about afixed post 4, the turntable being supported on rollers 5 which are inannular series beneath it (FIG. 2). Carried by the turntable is anannular indexing plate 6 shown in dotted lines in FIG. I. This plate hasshoulders at 7 corresponding in number to the number of stations anddisposed to be engaged by the head 8 on ram 10 for the stepped indexingadvance of the turntable through an angle equal to the angular spacingbetween stations. In accordance with conventional practice, stops 11 aredesirably provided to assure accuracy of registration.

It is also desirable to 'provide an interlock to assure that theturntable will not be indexed until the operations at all of the severalstations have been completed. If the indexing is controlled manually,this may involve no more than the provision of pushbuttons at theseveral stations which cause illumination of a succession of lights totell the operator who controls ram 10 that all is in readiness for theindexing operation. If the operation is controlled mechanically, therecan be signals given at the several stations which are connected inseries in the circuit which energizes ram 10. Thus the relay circuitwill be completed to energize ram It) only when all of the relays areenergized.

The turntable 2 is provided with pattern plate racks 12 corresponding innumber to the number of stations. Each rack is equipped with rollers 14providing a way upon which the respective pattern plates 16 may rollbetween an advanced position for use and a retracted position forstorage. In the retracted position, each pattern plate is on theturntable 2. In the advanced position, the pattern plate has left theturntable under thrust of a ram as shown at Station I in FIG. 1. Thepattern plates carry appropriate patterns 18.

Projecting radially from the turntable 2 are pairs of arms 20 forsupporting between them pairs of mold boxes 22, 24 which can be rotatedin unison for 90, and can be brought together and separated as bestshown in FIGS. 7 and 8. The arms 20 support bearings 26 for trunnions 28which support guide channels 30, one of which is shown at the left inFIG. 8, it being understood that a similar arrangement is at the right.Reciprocable in each guide channel is a bearing block 32 which normallyis in a position opposite the trunnion. This position is defined byimpositive detents consisting of the springpressed balls 34 engaged inpockets 36 in the opposite faces of block 32. The block is elevated fromthis position by ram 80 at only one of the several stations and this ramcontrols its return movement.

Carried by each block 32 is a transverse angle bar 42 which supportsrollers 44 providing a way along which one of the pattern plates 16 isreciprocable from the storage position of FIG. 9 to the position of useshown in FIG. 11.

The angle bar 42 also supports vertical guide rods 48 engaged bybearings at the ends of arms 50 which project from the sides of therespective boxes 22 and 24 as shown in FIG. 8. A ram 52 connected withthe box 24 has its plunger 54 engaged with block 32 for the raising andlowering of box 24. Similarly the ram 56 connected with box 22 has itsplunger 58 connected with block 32 for the raising and lowering of box22.

For bodily rotation of the mold box assembly, a motor 60, preferably afluid pressure motor, has its output shaft 62 connected with trunnion 28to turn the guide channel 30 through an arc of 90 to move the boxassembly from the position shown at the left in FIG. 2 to the positionshown at the right of FIG. 2 (and return). Flexible hose connections 64'are used as leads to the various rams and to the motor 60 and to thevent chambers 66 and 68 provided in the ends of boxes 22 and 24. Throughcertain of the hose connections, air escaping from the boxes while theboxes are being filled with sand is carried to a three-way valve 70having an atmospheric exhaust port 72. Later, when it is desired todischarge the molds from these boxes, the valve 70 connects the chambers66 and 68 with fluid supply line 74.

At Station ll, boxes 22 and 24 previously assembled on the pattern plate16, are filled with sand. As already stated, these boxes are open ended.When assembled with the pattern plate 16, they are rotated to stand onedge as shown in FIGS. 3, 4 and 5 and the whole assembly is thenelevated by the ram 80 to engage the filling port 82 at the end of eachbox with the respective sand supply nozzle 84. Sand will be suppliedthrough nozzles 84, preferably in accordance with the disclosure of thecompanion application above identified. However, before the sand can beadmitted to the boxes, the open ends of the boxes must be closed. Theopposing ram heads 88 have spring biased seal frames 90 which engage themargins of the boxes about their open ends before the surfaces 92 of theheads 88 close the boxes. Sand is then injected under pressure asindicated by the arrows 94 in FIG. 4, the air within the boxes escapingthrough the chambers 66 and 68 and the hoses 64 to the three-way valve70 and being discharged through the exhaust 72 to the atmosphere.

When the boxes are completely filled with sand about the pattern 18, therams 88 are further advanced from the positions of FIG. 4 to thepositions of FIG. 5. The seal frames 90 cannot partake of the advance,being engaged with the respec tive boxes. However, the ram faces 92 passtelescopically into the boxes as shown in FIG. 5 to compress the sand.When this has been accomplished, the rams 88 are retracted to theinitial positions in which they are illustrated in FIG. 3 and thesandfilled boxes 22 and 24 are lowered from the position of FIG. 3 tothe position of FIG. 2. They are now free to rotate 90 so that they willbe horizontal as in FIG. 8 instead of upright as in FIGS. 2 to 5.

The sequence of operation is illustrated diagrammatically in FIGS. 9 to25.

At Station I, the boxes and patterns are cleaned of sand from theprevious operation. This may be done by any convenient means such as theair jets 96. The pattern plates 16 and the pattern mounted thereon arethen slid forwardly on the supporting rolls above described by a ram 15which moves the pattern plate from the storage rack 12 on the turntableto the rollers 44 on the a rms 42 which are parallel to and intermediatethe boxes 22 and 24, as best shown in FIG. 8. The pattern plate is thenin the position shown in dotted lines in FIG. 10.

The open ended boxes 22 and 24 are now closed upon the pattern plate 16,as shown in FIG. 11.

Here the motor 60 is energized to rotate the box assembly from itsinitial horizontal position to the on-edge position shown in FIG. 12 soports 82 for the filling of each box are disposed upwardly. Theturntable then indexes to advance the closed assembly of FIG. 11 toStation II.

Operation of ram now lifts the assembly from the position of FIG. 13 tothe position of FIG. 14 to engage the box sides about ports 82 with thefilling nozzles 84 Immediately the closure rams 88 move in to engage theseal rings 90 with the margins of the boxes and to dispose the closuresurfaces 92 across the initially open ends of the boxes. With the partsin the position of FIG. 4, sand is injected through the nozzles 84 andthe air displaced from the boxes escapes to atmosphere through the valve70 as above described.

The boxes being completely filled with sand as shown in FIG. 14, therams 88 are advanced further as indicated in FIG. 15 to compact the sandaround the respective patterns 18. Rams 88 are then retracted out of theboxes and the elevator ram 80 is lowered to restore the box assembly toits original height. It is preferably at this point, with the boxesstill on edge, that the sprue basin or opening is formed in any desiredmanner (indicated diagrammatically by reamer 101). The motor 60 is thenreversed to restore the boxes to their initial horizontal position asshown in FIG. 17. This occurs, desirably, at Station Ill.

Still at Station III, the rams 52 and 56 are actuated to open the moldby raising box 24 and lowering box 22 as shown in FIG. 18. The ram 102is then advanced to engage the pattern plate 16 to displace it frombetween the boxes 22 and 24 and to restore it to the storage rack on theturntable )FIG. 19).

The turntable now indexes to move the boxes and molds to Station IV andthe cores 103, if any, are positioned in the openings left by thepatterns 18 (FIG. 20). This operation is usually manual. Still atStation IV, the box 24 is now ongaged with box 22 to close the mold(FIG. 21).

The assembly of boxes and mold is still supported on the turntable arms20 at a level higher than that of the discharge table 112. When theturntable has rotated to bring the assembly to Station V, a normallyretracted withdrawal yoke 114 which is U-shaped in plan is advanced fromthe position of FIG. 22 to that of FIG. 23 where it is positioned toreceive the finished sand molds. At this point, the table 116 ofelevator ram 118 is raised through the yoke into engagement with thesand mold 120 which is in box 22. At the same time, a complementaryejector plate 122 of ram 126 moves down into engagement with the sandmold 128 which is in box 24. The movement of the ejector plate 122continues, forcing downwardly the molds 128 and 120 and the elevatortable 116 until the table registers with the withdrawal table 112 asshown in FIG. 24. The completed mold is now in the plane of yoke 114.The boxes 24 and 22 are empty. The discharge of the finished molds fromthe boxes may be facilitated by the use of the three-way valve 70 toconnect the pressure line 74 through hoses 64 with the respective ventchambers 66 and 68 (FIGS.7and 4).

Still at Station V, the yoke 114 is moved by its ram 130 toward the leftas viewed in FIGS. 24 and 25, thereby withdrawing the mold from table116 of elevator I18 beneath -the boxes 22 and 24. Movement of the moldjust finished in the direction of withdrawal across the table 112propels in advance of its on said table the molds previously deliveredto the table in the manner described (FIG. 25).

The next indexing movement of the turntable 2 restores the boxes whichhave been under discussion back to Station I in readiness for arepetition of of the sequence. It will be understood that in each of thefive selected points on the turntable which registers with the fivestations above described, there is a similar series of boxes and similarcontrol mechanism so that with each periodical indexing movement anothermold is completed and withdrawn for the pouring of metal into its sprueopening.

If desired, the method herein disclosed may be practiced by replacingpermanent boxes for flaskless molds with frames to receive tight flaskswhich will produce tight flask molds.

The operation would still involve the 90 rotation of the flaslocarryingframes in exactly the manner in which the permanent boxes are rotated inthe manufacture of flaskless molds. The operation will then be asfollows:

At Station I tight flasks and pattern will be positioned, assembled androtated 90. The operations at the other stations will be as describedexcept at Station V the complete tight flask mold will be dischargedinstead of pushing out the flaskless mold as described.

If the core setting time exceeds the. machine cycle, the unit can beoperated as follows:

At Station I the drag flask will be positioned and the pattern drawn atStation V will be placed on it. At Station I], the cope flask will bepositioned and closed on the pattern and the assembly will then berotated 90 as above-described to register its sand receiving ports withthe supply nozzles. At Station III, sand will be injected thus makingthe mold exactly as above described. At Station IV, the assembly will berotated back 90" and the cope mold will be drawn and pushed down aconveyor to a remote closing station. At Station V, the drag mold willbe lowered from the pattern and pushed a conveyor to the closingstation, the pattern thereupon being transferred back to Station I.There can be any desired number of core setting stations to accommodateadditional core setters when the core setting time exceeds the machinecycle time.

Obviously, from a method standpoint, the significant 90 rotation isexactly the same as above described and it serves the same purpose.

I claim:

l. A device for making sand molds which comprises permanent form boxeshaving end filler openings, a turntable comprising at angularly spacedstations a plurality of pairs of means for supporting the form boxes forrelative movement on predetermined paths to and from positions forcooperation as an assembly to make a complete mold, operating means foractuating the form boxes to said positions and for retracting them fromsaid positions, means for storing pattern plates on the turntableadjacent the path of such movement, means providing a way on which apattern plate is movable between a storage position and a positionintervening between the form boxes as a part of said assembly when thelatter are in the said positions for cooperation, means for advancingand retracting the pattern plate upon said way, means for filling theform boxes through respective openings with sand at opposite sides ofthe plate, opposing means movable toward the plate and into the formboxes for compressing the sand to make half molds in the respective formboxes, the said actuating means being adapted to separate the form boxesand half molds from the pattern plate and to retract the pattern platefrom between the form boxes and the half molds, means for reassemblingthe form boxes and half molds, a mold receiving table adjacent theturntable, means for positioning the form boxes above it, and

means for ejecting the assembled half molds onto the receiving tablefrom the form boxes.

2. Mold making apparatus according to claim in which the means forfilling the form boxes includes means for pneumatically extruding sandfrom a magazine and means for venting air from the box, said apparatusfurther including means for supplying ejection fluid under compressionthrough said venting means concurrently with the application ofmechanical ejection pressure for displacing from the form boxes themolds formed therein.

3. Apparatus according to claim I in which the means for supporting theform boxes includes a means for rotating the assembly of form boxes andpattern plate from horizontal to vertical.

4. Apparatus according to claim I in which the means supporting the formboxes includes means for rotating the form boxes between generallyhorizontal and generally vertical positions, the form boxes having endfilling ports and the apparatus including separate nozzles for therespective form boxes, and means for effecting relative movement in adirection to engage said nozzles with the form boxes.

5. Apparatus according to claim I in which the supporting meanscomprises a turntable having a plurality of pattern plate ways generallycomprising radially projecting arms, the said supporting means furtherincluding individual form box supports mounted on said arms for movementto and from each other, said pattern plate storing means comprising away carried in part by said turntable and in part by said arms, the saidform boxes being presented by turntable rotation successively to saidnozzles.

6. Apparatus according to claim 1 in which the form boxes have openfaces and the opposing means for compressing the sand comprises a pairof platens and means supporting the platen between first fully retractedpositions, second positions in which the platens are advanced from theretracted positions into substantial registry with the form boxes toclose the faces thereof to confine the sand, and third positions inwhich the platens are advanced telescopically into the form boxes forcompression of sand therein, together with means for times movement ofsaid platens between the several positions: aforesaid, said means forfilling the form boxes with sand and said platens having supportingmeans adjacent the turntable and with which successive assemblies ofform boxes and pattern plates register in one position of the turntable.

7. Apparatus according to claim 6 in which the respective platens areprovided with edge seals yieldably carried thereby and engageable withthe margins of respective form boxes as the respective platens are inthe stated second and third positions.

8. Apparatus according to claim 6 in further combination with means ofintroducing sand forcibly into the respective form boxes and for ventingair from the form boxes as the form boxes are filled with sand, andmeans for subsequently introducing pressure fluid through said ventingmeans into the form boxes concurrently with mechanical displacement ofmolds from the form boxes.

9. Mold making apparatus comprising a turntable, pairs of open formboxes, supports for the form boxes projecting from the turntable, meansfor indexing the turntable to register the pairs of form boxes withsuccessive stations, the said supports including means for effectingrelative movement of the form boxes between retracting and assembledpositions, means for rotating the form boxes in assembled position toexpose their open faces laterally, platens mounted for movement to andfrom the open faces of the form boxes when the latter are exposedlaterally, said platens being adapted to provide temporary closure forsaid open faces, sand supply means including nozzles above the form boxassembly for injecting the sand into the respective form boxes when theopen faces thereof have been temporarily closed by said platens, meansfor raising the assembly of the form boxes and platens into engagementwith said nozzles, means for lowering the assembly of form boxes andplatens from the nozzles after the form boxes have been filled withsand, means for advancing the platen telescopically into the form boxesfor the compression of the sand therein, means for with drawing theplatens from the form boxes, means for rotating the assembly of formboxes to initial horizontal position, a withdrawal table at one of thestations, an elevator imposed between the withdrawal table and theturntable in a position to underlie the assembly of form boxes, meansfor moving the elevator upwardly into engagement with a sand mold formedin the form boxes, an opposing platen mounted for vertical movementabove the elevator, means for lowering the last platen to force the sandmold and the elevator downwardly for ejection of the mold from the formboxes, a withdrawal yoke movable along the table between an advancedposition adjacent the turntable and a retracted position remote from theturntable, means for positioning said yoke in advanced position duringupward and downward movement of the elevator and means for actuatingsaid yoke toward retracted position when the mold ejected from the formbox is at the level of the withdrawal table, whereby such mold is pulledacross the elevator onto the withdrawal table.

10. A device for making sand molds which comprises complementaryopen-faced form boxes having air vents and having sand-receivingopenings in corresponding ends, a pattern plate with opposite faces,means for introducing the pattern plate between such boxes and forclosing the boxes upon the pattern plate to constitute a mold assembly,said sand-receiving openings being remote from the pattern plates, meansmounting the assembly for rotation between a first position in which thepattern plate is substantially upright and a second position in whichthe plate is generally horizontal, means for introducing sand into therespective mold boxes downwardly through said openings when the assemblyis in said first position, ram means mounted for operation oppositelythrough said boxes toward the pattern plate for compressing sand againstthe pattern plate and making molds in said boxes,

means for rotating the assembly to the second position, means forseparating the said boxes and molds from the pattern plate, means forretracting the pattern plate from between the boxes and molds, means forreassembling the boxes and molds with each other, and means forwithdrawing the assembled molds from the assembled boxes.

11. A device for making sand molds which comprises a turntable, pairs ofopen-faced form boxes with end filler openings at angularly spacedpoints upon the turntable, a pattern plate for assembly with a pair ofform boxes at each such point, a way upon which the pattern plate isreciprocable generally radially with reference to the turntable to andfrom position between the form boxes of the respective pairs, means foradvancing a pattern plate between its respective boxes and for closingthe boxes upon such pattern plate to constitute an assembly, means at apredetermined station beside the turntable for introducing sand into therespective boxes of the assembly, means for rotating the assemblyadjacent said station to present the respective filling openings of thesaid boxes upwardly to the sand introducing means, opposing rams at saidstation movable toward each other into engagement with the upright boxespreliminary to the filling thereof, means for further advancing saidrams into the filled boxes for compression of sand filled into saidboxes to form molds against the pattern plate, means for retracting saidrams from the boxes, means for rotating the assembly to a generallyhorizontal position and moving it back onto the turntable, means forseparating the boxes and for withdrawing the intervening pattern plateupon its way, means for rotating the remaining box and mold assemblyoutwardly of the turntable, a receiving table at another stationadjacent the turntable with which said assembly registers when thusrotated outwardly, and means for ejecting from said boxes the moldsformed therein.

1. A device for making sand molds which comprises permanent form boxeshaving end filler openings, a turntable comprising at angularly spacedstations a plurality of pairs of means for supporting the form boxes forrelative movement on predetermined paths to and from positions forcooperation as an assembly to make a complete mold, operating means foractuating the form boxes to said positions and for retracting them fromsaid positions, means for storing pattern plates on the turntableadjacent the path of such movement, means providing a way on which apattern plate is movable between a storage position and a positionintervening between the form boxes as a part of said assembly when thelatter are in the said positions for cooperation, means for advancingand retracting the pattern plate upon said way, means for filling theform boxes through respective openings with sand at opposite sides ofthe plate, opposing means movable toward the plate and into the formboxes for compressing the sand to make half molds in the respective formboxes, the said actuating means being adapted to separate the form boxesand half molds from the pattern plate and to retract the pattern platefrom between the form boxes and the half molds, means for reassemblingthe form boxes and half molds, a mold receiving table adjacent theturntable, means for positioning the form boxes above it, and means forejecting the assembled half molds onto the receiving table from the formboxes.
 2. Mold making apparatus according to claim in which the meansfor filling the form boxes includes means for pneumatically extrudingsand from a magazine and means for venting air from the box, saidapparatus further including means for supplying ejection fluid undercompression through said venting means concurrently with the applicationof mechanical ejection pressure for displacing from the form boxes themolds formed therein.
 3. Apparatus according to claim 1 in which themeans for supporting the form boxes includes a means for rotating theassembly of form boxes and pattern plate from horizontal to vertical. 4.Apparatus according to claim 1 in which the means supporting the formboxes includes means for rotating the form boxes between generallyhorizontal and generally vertical positions, the form boxes having endfilling ports and the apparatus including separate nozzles for therespective form boxes, and means for effecting relative movement in adirection to engage said nozzles with the form boxes.
 5. Apparatusaccording to claim 1 in which the supporting means comprises a turntablehaving a plurality of pattern plate ways generally comprising radiallyprojecting arms, the said supporting means further including individualform box supports mounted on said arms for movement to and from eachother, said pattern plate storing means comprising a way carried in partby said turntable and in part by said arms, the said form boxes beingpresented by turntable rotation successively to said nozzles. 6.Apparatus according to claim 1 in which the form boxes have open facesand the opposing means for compressing the sand comprises a pair ofplatens and means supporting the platen between first fully retractedpositions, second positions in which the platens are advanced from theretracted positions into substantial registry with the form boxes toclose the faces thereof to confine the sand, and third positions inwhich the platens are advanced telescopically into the form boxes forcomPression of sand therein, together with means for times movement ofsaid platens between the several positions aforesaid, said means forfilling the form boxes with sand and said platens having supportingmeans adjacent the turntable and with which successive assemblies ofform boxes and pattern plates register in one position of the turntable.7. Apparatus according to claim 6 in which the respective platens areprovided with edge seals yieldably carried thereby and engageable withthe margins of respective form boxes as the respective platens are inthe stated second and third positions.
 8. Apparatus according to claim 6in further combination with means of introducing sand forcibly into therespective form boxes and for venting air from the form boxes as theform boxes are filled with sand, and means for subsequently introducingpressure fluid through said venting means into the form boxesconcurrently with mechanical displacement of molds from the form boxes.9. Mold making apparatus comprising a turntable, pairs of open formboxes, supports for the form boxes projecting from the turntable, meansfor indexing the turntable to register the pairs of form boxes withsuccessive stations, the said supports including means for effectingrelative movement of the form boxes between retracting and assembledpositions, means for rotating the form boxes in assembled position toexpose their open faces laterally, platens mounted for movement to andfrom the open faces of the form boxes when the latter are exposedlaterally, said platens being adapted to provide temporary closure forsaid open faces, sand supply means including nozzles above the form boxassembly for injecting the sand into the respective form boxes when theopen faces thereof have been temporarily closed by said platens, meansfor raising the assembly of the form boxes and platens into engagementwith said nozzles, means for lowering the assembly of form boxes andplatens from the nozzles after the form boxes have been filled withsand, means for advancing the platen telescopically into the form boxesfor the compression of the sand therein, means for with drawing theplatens from the form boxes, means for rotating the assembly of formboxes to initial horizontal position, a withdrawal table at one of thestations, an elevator imposed between the withdrawal table and theturntable in a position to underlie the assembly of form boxes, meansfor moving the elevator upwardly into engagement with a sand mold formedin the form boxes, an opposing platen mounted for vertical movementabove the elevator, means for lowering the last platen to force the sandmold and the elevator downwardly for ejection of the mold from the formboxes, a withdrawal yoke movable along the table between an advancedposition adjacent the turntable and a retracted position remote from theturntable, means for positioning said yoke in advanced position duringupward and downward movement of the elevator and means for actuatingsaid yoke toward retracted position when the mold ejected from the formbox is at the level of the withdrawal table, whereby such mold is pulledacross the elevator onto the withdrawal table.
 10. A device for makingsand molds which comprises complementary open-faced form boxes havingair vents and having sand-receiving openings in corresponding ends, apattern plate with opposite faces, means for introducing the patternplate between such boxes and for closing the boxes upon the patternplate to constitute a mold assembly, said sand-receiving openings beingremote from the pattern plates, means mounting the assembly for rotationbetween a first position in which the pattern plate is substantiallyupright and a second position in which the plate is generallyhorizontal, means for introducing sand into the respective mold boxesdownwardly through said openings when the assembly is in said firstposition, ram means mounted for operation oppositely through said boxestoward the pattern plate for compressing Sand against the pattern plateand making molds in said boxes, means for rotating the assembly to thesecond position, means for separating the said boxes and molds from thepattern plate, means for retracting the pattern plate from between theboxes and molds, means for reassembling the boxes and molds with eachother, and means for withdrawing the assembled molds from the assembledboxes.
 11. A device for making sand molds which comprises a turntable,pairs of open-faced form boxes with end filler openings at angularlyspaced points upon the turntable, a pattern plate for assembly with apair of form boxes at each such point, a way upon which the patternplate is reciprocable generally radially with reference to the turntableto and from position between the form boxes of the respective pairs,means for advancing a pattern plate between its respective boxes and forclosing the boxes upon such pattern plate to constitute an assembly,means at a predetermined station beside the turntable for introducingsand into the respective boxes of the assembly, means for rotating theassembly adjacent said station to present the respective fillingopenings of the said boxes upwardly to the sand introducing means,opposing rams at said station movable toward each other into engagementwith the upright boxes preliminary to the filling thereof, means forfurther advancing said rams into the filled boxes for compression ofsand filled into said boxes to form molds against the pattern plate,means for retracting said rams from the boxes, means for rotating theassembly to a generally horizontal position and moving it back onto theturntable, means for separating the boxes and for withdrawing theintervening pattern plate upon its way, means for rotating the remainingbox and mold assembly outwardly of the turntable, a receiving table atanother station adjacent the turntable with which said assemblyregisters when thus rotated outwardly, and means for ejecting from saidboxes the molds formed therein.